The present study was planned as a superiority trial. When the 20 mm difference in VAS is accepted as clinically significant and the standard deviation is accepted as 25 mm, 35 patients are needed with each group with 95% power. All the analysis were implemented according to the intention to treat analysis. The precise of differences between time intervals within groups and between groups and statistical significance were expressed by 95% confidence intervals (95% CI). All tests of significance were two sided.